Telephonic circuit and apparatus



(No Model.)

J. B. WOOD.

TBLEPHONIG CIRCUIT AND APPARATUS. No. 3 0 763. lyl Patented N0v.885.

fnvenior.

n, PETERS. Photo-Lithographer. WaahInglan, ac.

TINTTED STATES PATENT 0mm.

JOHN B. woo'n, OF MONTREAL, QUEBEC, OA'NADA.

TELEPHONIC CIRCUIT AND APPARATUS.

ESPECIFICATIQN forming part of Letters Patent No. 330,763, dated November 17, 1885. Application filed September 2, 1833. Serial No. 176,012. (No'modellh I To all whom it may concern:

Be it known that I, JOHN BAXTER WOOD, of the city of Montreal, in the District of Montreal and Province of Quebec, in the Domin- ,5 ion of Canada, have invented certain new and useful Improvements in Telephonic Circuits and Apparatus; and I do hereby declare that the following is a full, clear, and exact description of the same.

This invention relates to circuits and apparatus used in telephonic intercommunication, and has for its object to provide a simple and efficient system which shall be specially adapted to stores and other buildings where a cen tral office is not used, and to villages and like places where a number of stations are to be placed in communication with each other.

By my invention a person at one station can call and place himself in connection and converse with any one or more of the other stations in the system without cutting in or disturbing the remainder. To this end I have a separate line running from each station to each one of the others, and each station is provided with a call-bell, a transmitting and receiving instrument, and a case containing electro-magnets, armatures, and connecting drop-levers in number to correspond with the number of stations in the system, and pushbuttons numbered to agree with the stationnumbers, each of which, when pressed, will operate to release one of the drop-levers and throw the required line into circuit.

For full comprehension of my improvements reference must be had to the accompanying drawings, in which Figure l is a longitudinal sectional elevation of the apparatus employed at each station; Fig. 2, a plan of same; Fig. 3, a view representing two cross-sections of Fig. 1, taken on the chain-lines shown, with connecting-wires making a complete circuit at one station; and Fig. 4, a diagram of my system showing connections for five stations.

Similar letters of reference indicate like parts in all the figures.

The different stations are numbered 1, 2, 3, 4, and 5, respectively, and for clearness of description I have assumed that the apparatus shown in Figs. 1, 2, and 3 is that used at station 1. Four push-buttons, 2 3 4 5-1. 6., one

for each of the other stationsare provided,

a spiral spring, a, which serves to retain the button in its normal position, which is out of .contact with an armature placed underneath,

each within the case. These armatures are marked A A A A and for each armature there is a pair of magnets, M M, &c., said magnets being electrically connected in the system in the usual manner,which is well understood. These magnets are preferably carried on a frame, F, attached to the interior of the case A, and near the extremity of this frame are pivoted drop-levers L L 850., of somewhat the shape shown, their free ends being arranged to engage with the ends of the several armatures A A &c.,, and thus be held in the normal circuit when the push-buttons are up and the armatures out of connection with their magnets. These drop-levers when up are in electrical connection with the magnets to which they relate. The rest of the apparatus used at each station in my system are a pivoted lever or rod, It, operated bya connecting-lever,which projects through an aperture in the case A, and is furnished with a finger-piece, r, to replace the drop-levers, a call-bell, B, and a hooklever, H, for supporting the instrument T.

The call-bell is shown in Figs. 1 and 3, and may be of any approved construction, and at each station is put into circuit by means of a bell-button, N, (in the manner hereinafter explained,) a spring, a, beingplaced upon its spindle to keep the bell normally out of circuit with the battery Z.

The hook-lever H may be of thefkind now generally used in telephoneapparatus, the

arrangement shown in Fig. 3 being about what I consider necessary in carrying out my invention. The lever is there fulcrumed in a short bracket, h, attached to the interior'of the box A, and has a spring, h, connected thereto for the purpose of throwing said hooklever into circuitwhen the instrument T is removed from the fork or hook, and thus es tablish the circuit in the instrument necessary for conversation. Normally said hook-lever is in connection with the line, as shown, and with the bell-button through a short flexible spring, n, attached to the end of the bellbutton spindle, the battery being out of cirinthe drawings, as any electrician will understand how this can be connected. I may say, however, that I prefer to use a combined transmitter and receiver, and so arrange my connections that both will be thrown into circuit when the hook-lever H is released. Suitable return and ground wires are of course provided, and these are connected in the manner well known to electricians.

The operation of my invention is as follows:

Suppose. a person at station 1 wishes to,con-

verse with another at, say, station 3. He will press button 3 in instrument No. 1. This will release the drop-lever L and cause the spring S at that point to form contact with spring S, and thus throw line 3 into connection. He then compresses bell button N in his own instrument, (No. 1,) which throws battery Z into circuit, and magnet No. 1 in box at station 3 is at once aifected, so as to attract its armature and release the drop lever in connection therewith, (this latter acting through the springs to put line from N0. 3 to No. 1 into circuit,) the bell at No. 3 ringing at the same time and attention of person at No. 3 directed to the fact that No. 1 desires communication. be touched to indicate attention, and both instruments being then lifted off the hooks,they are brought into the circuit, and the bells and call-keys disconnected. The conversation being finished, the instruments '1 are hung up, and the drops at the two connected stations are replaced by both operators pressing the finger-pieces r in their respective boxes, and thus causing the rods R to rise and carry the drop-levers,previously resting upon said rods, back to connection with their armatures, said drop-levers carrying back with them the springs S, and breaking their contact with the springs S, and restoring the lines to their normal condition.

No. 3. bell-button may then By referring to Fig. 3, the manner of connecting the battery,bells, and instruments will be clearly seen and understood;butI may explain that when the bell-button N is compressed and the batteryline Bl connected at the point Z, the spring n on the end of the button-spindle N, being very flexible, does not compress the hook-lever H, but merely retains the circuit already existing through said lever and the line X.

When the instrument '1 is removed from the hook, the spring h draws the lever into connection with the line W, running to the instrument, and the spring 'n being thus thrown out of connection, the line Y (connected to the other pole of the instrument) is the one which establishes the circuit.

Should a person at any of the other stations in my system attempt to connect with either No. 1 or No. 3 while they are conversing, when the call-key at the out station was compressed, the battery-circuit would be cut in, and asharp click in No. 1 and No. 3 telephone would warn them that another instrument was connected.

It must be understood that I do not limit myself to the details of construction and the precise manner of making the different connections shown in the drawings, as these only illustrate one way of carrying out my invention, and may be varied to suit the ideas of 0 the electrician, providing that the essential features of having a wire from each station run to each of the others in the system and the arrangement whereby-each may be put into communication with any one of the others by the person calling be preserved.

What I claim, and desire to secure by Letters Patent, is as follows:

A system of telephonic intercommunication consisting of a'number of stations each rco connected to each one of the others by separate wires, (without the intervention of a central ofiice,) and at each station, a call-bell and telephonic apparatus normally out of circuit, and a number of magnets, armatures, dropr05 levers, and push-buttons to correspond with number-of stations, each of said push-buttons operating to cause one of said drop-levers to fall, and thereby connect the calling station with any of the others at the will of the operar 10 tor, substantially in the manner specified.

Montreal, 12th day of August, 1885.

JOHN B. WOOD.

Witnesses:

R. A. KELLOND, O. P. MoDowELL. 

